Cytochrome P450

Part B Q1. The normal dose of paracetamol is very safe to use and it is not over 4g per 24 hours; however, when the patient take more than 6g per 24 hours of paracetamol, the liver necrosis will happen within 10 to 12 hours and liver damage may occur within 24 to 48 hours. For the metabolism, most of the paracetamol is converted to nontoxic metabolites by the phase II conjugation of glucuronide and sulfate and a small amount of paracetamol is oxidized by the Cytochrome P450 (CYP) enzymes in the phase I metabolism. In this phase, CYP1A2 and CYP2E1 enzymes convert paracetamol to N-acetyl-p-benzoquinoneimine (NAPBQI) which is highly toxic substances. NAPBQI will rapidly enter the phase II conjugation of glucuronide and detoxified in the liver…

Steroid use for high school sports can have many negative affects on your body, that people don’t realize. The human body reacts differently to different things. People take steroids to help their performance in sports. They may also take them to enlarge their muscles. What they don’t know is that it has more than just positive effects. They are too caught up in their appearance to even realize all of the side effects it can put out. Males are proven to take most of the blame for the use of…

CYP2D6 is a Phase I oxidative metabolism enzyme that is clinically important because about 20-25% of clinically used drug are metabolized by the CYP2D6 enzyme. CYP2D6 substrates are typically lipophilic and include drugs such as antidepressants, antipsychotics, antiarrhythmic, antiemetic, and opioids. The exact clinical effect of the polymorphism is dependent on the drug and the variant alleles expressed because individual allele variants can lead to a range of metabolic ability from ultrarapid…

hours exposer to SK-N-SH cells. Exposed differentiated neuronal cells showed significant dose-dependent increase levels of reactive oxygen species (ROS), even at with sub-lethal concentration (DBT, and Ret). Intracellular superoxide measurement analyses by Mitosox stained cells revealed similar patterns of ROS. Though ROS production contributes significantly to induced apoptotic cell death, we hypothesized that PACs trigger ROS production, leading to the activation of apoptotic signaling…

role in biological systems to catalyze and control different reactions. The study of enzymes’ behaviors toward substrates and products is significant to understand various enzyme catalyzed reactions in living organisms. One of the most important enzymatic group is cytochrome P450 (CYP450) which contribute to the metabolism of many endogenous as well as exogenous substances such as drugs. Although there are several subtypes of CYP450 family, CYP450 1A1 is going to be discussed. Consequently, the…

Steroids are lipids because they are hydrophobic and difficult in water, but they do not feature lipids since they have a design composed of four fused rings. Cholesterol is the most frequent steroid and is the messenger to vitamin D, testosterone, estrogen, progesterone, aldosterone, cortisol, and animus salts. Cholesterol is a basic of the phospholipid bilayer and plays a role in the structure and function of membranes. Steroids are found in the brain and adjust electrical activity in the…

importance. Examples include : • Vitamin B12 • Chlorophyll • Haemoglobin • Myoglobin • Cytochromes Vitamin B12 is an important coordination compound found in biological systems. It is a exclusive biomolecule because no other vitamin contains a metal ion. This is the only naturally occurring organometallic compound found in biology. Its common feature is that its metal ion is enclosed in a macrocyclic ligand. It is surely the most complex non polymeric compound and is devoid of protein…

• The mechanism of action of cyclophosphamide is an alkylating agent that causes cross-linkage of DNA strands, thereby blocking synthesis of DNA, RNA, and protein. Has pronounced antineoplastic effects and immunosuppressive activity. EFFECTS?? • The Pharmacodynamics of the cyclophosphamide includes the absorption from the GI tack. The drug is widely distributed going to the brain, and breast milk. Should be careful while taking cyclophosphamide because it does cross the placenta. The drug…

Describe the biotransformation (what enzyme performs this reaction, etc). If the major metabolite is unknown, predict a biotransformation. Losartan and EXP3174 metabolite1 Losartan is converted to the EXP3174 metabolite by P450 isozymes (CYP3A4 & CYP2C9) The oxidation of the OH group in Losartan to a carboxylic acid. The bioavailability or clearance can commonly be altered by a pathophysiologic change or co-administration of a second drug? Give an example of a disease/drug, drug/drug, or…

cases individual animals, exist with regard to AF metabolism. Factors influencing AF metabolism include species, sex, age, health, and diet. The pure form of AFB1 is not mutagenic and its biotransformation in mammalian tissues is primarily accomplished by microsomal cytochrome P450 monooxygenases. The P450 enzymes and their subfamilies are found at different concentrations in most tissues of various animal species with abundance generally in the liver (Eaton et al., 1994). Four metabolic…